red n black

[Trav001]

G day all, building up a 253 V8 for my VH Brock ADP 1 project and got a few questions.

1: does all the ports on a 4 barrell manifold of a VL's black motor fit a red 253?

2: if red heads dont match up, will the black heads of the 4.9L fit the 253? (talking about the valve size difference)

 

[ari666]

253 and 308 heads are identical. only differences in heads are;

HT-HQ: no egr crossover, single bolt in the middle
HJ-VB: u shaped egr crossover, single bolt in the middle
VK esk: L shaped egr crossover, two bolts in the middle
VN, totally different.

there are a few combustion chamber differences etc. as far as i am aware he only valve differences are for the higher performance L34 heads and VN's.

so the answer to the question is;

1: im pretty sure NO, the ports will fit, but the two center bolts on the VL manifold will not fit the single bolt on red heads (assuming they are pre-egr red heads) and plus the crossover on your manifold will be blowing and sucking vacuum into the valley, which you DONT want.
2: yep, black heads will fit as long as they are the old style and not the later VN style.

 

[Trav001]

yeah they re the old style heads im worried bout the valve hitting the top of the block since the bore siZe is different. the red heads are off a HZ the black heads are out of a HDT VL and I got another set of red heads out of a LX

 

[ari666]

bore size doesnt make any difference to valve clearance, its all down to cam shaft and TDC. you will need to make sure your cam doesnt lift too high and that its timing is set correctly. other than that unless you have some serious dome on your pistons then there is no way for the valves to hit.

i have the largest valves for cast heads and flat tops and there is still loads of clearance at TDC

edit: OH, do you mean the valve hitting the actual block? there is no chance of that happening at all. 253 and 308 are exactly the same heads. all the way up to VN. (even though the 253 was dropped by VL)

 

[SL/ENUT]

You will find that the VL heads aren't much chop on the 253, valves are to big.

 

[Trav001]

Ta for the advice. :thumbsup: pretty sure its got EGR

 

[ari666]

hope this helps ya, this is what the middle ports look like on your manifold to help determin whether it has egr or not;

red inlet manifold centerbolt (viewed from the bottom) no egr crossover, one bolt

black inlet manifold (bottom as well) square egr crossover, two center bolts.

there is one more U shaped egr crossover port design too, but it has the same bolt holes as the black. i can take comparison pics of the two heads too, but i only have the red ones here. my black heads are at home. let me know if itll help ya.

 

[Trav001]

im 90% sure mines the same as the bottom pic. i'll check when i get home. thanks for the help :thumbsup: